Classifications

• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
  • G02B1/041—Lenses
  • G02B1/043—Contact lenses
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09B—ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES, e.g. PIGMENTS; MORDANTS; LAKES
  • C09B9/00—Esters or ester-salts of leuco compounds of vat dyestuffs
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/008—Preparing dyes in situ
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/22—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using vat dyestuffs including indigo
  • D06P1/28—Esters of vat dyestuffs
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/44—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders
  • D06P1/52—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders using compositions containing synthetic macromolecular substances
  • D06P1/5207—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • D06P1/5214—Polymers of unsaturated compounds containing no COOH groups or functional derivatives thereof
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/44—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders
  • D06P1/52—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders using compositions containing synthetic macromolecular substances
  • D06P1/5207—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • D06P1/5214—Polymers of unsaturated compounds containing no COOH groups or functional derivatives thereof
  • D06P1/5221—Polymers of unsaturated hydrocarbons, e.g. polystyrene polyalkylene
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/44—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders
  • D06P1/52—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders using compositions containing synthetic macromolecular substances
  • D06P1/5207—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • D06P1/5214—Polymers of unsaturated compounds containing no COOH groups or functional derivatives thereof
  • D06P1/5228—Polyalkenyl alcohols, e.g. PVA
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/44—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders
  • D06P1/52—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using insoluble pigments or auxiliary substances, e.g. binders using compositions containing synthetic macromolecular substances
  • D06P1/5207—Macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • D06P1/525—Polymers of unsaturated carboxylic acids or functional derivatives thereof
  • D06P1/5257—(Meth)acrylic acid
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P1/00—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed
  • D06P1/90—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using dyes dissolved in organic solvents or aqueous emulsions thereof
  • D06P1/92—General processes of dyeing or printing textiles, or general processes of dyeing leather, furs, or solid macromolecular substances in any form, classified according to the dyes, pigments, or auxiliary substances employed using dyes dissolved in organic solvents or aqueous emulsions thereof in organic solvents
  • D06P1/928—Solvents other than hydrocarbons
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P3/00—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated
  • D06P3/003—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated using vat or sulfur dyes
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P3/00—Special processes of dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form, classified according to the material treated
  • D06P3/34—Material containing ester groups
  • D06P3/343—Material containing ester groups using vat or sulfur dyes
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06P—DYEING OR PRINTING TEXTILES; DYEING LEATHER, FURS OR SOLID MACROMOLECULAR SUBSTANCES IN ANY FORM
  • D06P5/00—Other features in dyeing or printing textiles, or dyeing leather, furs, or solid macromolecular substances in any form

Definitions

• U.S. Pat. No. 4,891,046 describes tinting a hydrophilic contact lens with a dichlorotriazine dye in a two step procedure.
• the lens which is formed from a hydrophilic polymer obtained by the peroxide-initiated polymerization of a polymer forming composition, is immersed in an aqueous solution of dichlorotriazine dye. Under specific conditions, the dye diffuses into the lens.
• U.S. Pat. Nos. 5,151,106 and 5,292,350 describe methods for tinting a hydrophilic polymer by incorporating a reactive dye into monomers used during polymerization.
• the reactive dye is physically entrained within the polymer composition and, subsequently, the polymer composition is contacted with an aqueous solution of a base which catalyzes the covalent attachment of the reactive dye to the polymer.
• a base which catalyzes the covalent attachment of the reactive dye to the polymer.
• the --OH group of the hydroxyethyl methacrylate polymer under alkaline conditions, will form an ether bond with the reactive dye.
• This method requires the reactive dyes to be soluble in the monomer mix and requires exposure to a "fixative" environment during or after the lens hydration. According to U.S. Pat. No.
• European Patent No. 0 122 771 B discloses a process wherein the hydrogel material is simultaneously contacted with a swelling agent having a swelling power greater than water and a soluble leuco sulfate ester precursor of the insoluble vat dye in order to permit incorporation of the soluble leuco sulfate ester into the hydrogel material. Subsequently the hydrogel material is treated with an oxidizing agent to convert the soluble leuco sulfate ester to an insoluble vat dye wherein substantially all of the vat dye is physically locked within the hydrogel material. As is apparent this tinting process involves several separate process steps after formation of the hydrogel material.
• tint to hydrogel materials e.g., contact lenses
• methods for non-covalent incorporation of tint to hydrogel materials involve the use of fine dispersions/suspensions of monomer insoluble dyes into the prepolymer mix. Upon polymerization, the insoluble dye is dispersed throughout the hydrogel material.
• monomer insoluble dyes are subject to undesirable aggregate and agglomerate formation.
• this invention is directed to a method for the manufacture of tinted hydrogel materials which method comprises:
• the oxidation of the leuco sulfate ester of the vat dye in the monomer solution to the insoluble vat dye is initiated simultaneously with initiation of the polymerization of the monomer composition.
• the tinting process is simply incorporated into the polymerization process without the need for additional process steps either prior to or after polymerization.
• this invention is also directed to novel compositions for use in the methods described above.
• this invention is directed to a composition comprising a compatible hydrophilic ethylenically unsaturated monomer or mixture of monomers and from about 0.05 to about 0.5 weight percent of a leuco sulfate ester of a vat dye.
• a particularly preferred aspect of this process is the use of an oxidizing initiator which can operate both to oxidize the leuco sulfate ester of the vat dye and to polymerize the monomer solution.
• an oxidizing initiator which can operate both to oxidize the leuco sulfate ester of the vat dye and to polymerize the monomer solution.
• vat dyes or "water-insoluble vat dyes” refers to well known classes of dyes which are distinguished by the special method of application needed, a vatting operation. Vat dyes can be readily reduced to a water-soluble leuco form. Subsequent oxidation then produces the insoluble colored form of the dye.
• leuco sulfate esters of vat dyes refer to the well known water soluble salts of vat dyes. Upon hydrolysis and oxidation, the leuco sulfate ester of the vat dye is converted to the water insoluble form of the vat dye.
• a large variety of useful water soluble leuco sulfate esters have been devised and synthesized over the years. Many of these esters are commercially available and in sufficient colors so that mixtures of such esters are adequate to produce any desired range of hues.
• the particular leuco sulfate ester employed in this invention and the corresponding subsequent vat dye is not critical and includes, by way of example only, the following leuco sulfate esters of:
• solubilized leuco sulfate esters of vat dyes are exemplified by the diagrammatic formulas of the type shown below for solubilized ⁇ -2,2'(3H, 3'H)bisindole-3,3'-dione: ##STR1## and solubilized 6,15-dihydro-5,9,14,18-anthrazine-tetrone: ##STR2## and that the multiplicity of very hydrophilic sodium sulfate groups is responsible for the solubility of these materials in aqueous media.
• compatible hydrophilic ethylenically unsaturated monomer refers to hydrophilic ethylenically unsaturated monomers capable of solubilizing at least 0.05 weight percent of at least one leuco sulfate ester of a vat dye which monomers contain at least one hydrophilic functionality (e.g., a hydroxyl group, a carboxyl group, an amide group, etc.) which, when said monomers are incorporated in sufficient amounts into a polymer, renders the resulting polymer capable of absorbing at least 5 weight percent water.
• hydrophilic functionality e.g., a hydroxyl group, a carboxyl group, an amide group, etc.
• the resulting polymers will be able to absorb between 10 and 95 weight percent water and more preferably between 20 and 70 weight percent water.
• the compatible hydrophilic ethylenically unsaturated monomer will solubilize up to at least 0.5 weight percent of at least one leuco sulfate ester of a vat dye.
• Suitable compatible hydrophilic ethylenically unsaturated monomers for use herein are readily determined merely by ascertaining the solubility of a selected leuco sulfate ester of a vat dye in the monomer and determining the amount of water absorbed by a polymer of that monomer. Such determinations are well within the skill of the art.
• the particular compatible hydrophilic ethylenically unsaturated monomer for use in this invention is not critical and monomers suitable for use herein include, by way of example only, hydroxy lower alkyl acrylates or methacrylates, hydroxy lower alkoxy lower alkyl acrylates or methacrylates, and alkoxy lower alkyl acrylates or methacrylates.
• a “lower alkyl” or “lower alkoxy” is herein defined to mean an alkyl or alkoxy having from 1 to 6 carbon atoms.
• Specific hydrophilic monomers include hydroxyethyl methacrylate (HEMA), hydroxyethylacrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, butanediol monomethacrylate monoacrylate, glyceryl acrylate, glyceryl methacrylate, vinylpyrrolidone, N,N-dimethylacrylamide, and the like.
• HEMA hydroxyethyl methacrylate
• the hydroxyalkyl acrylates and methacrylate, particularly 2-hydroxyethyl methacrylate are generally preferred.
• Such monomers include styrene, acrylates or methacrylates such as methyl methacrylate, ethyl acrylate, isopropyl acrylate, propyl acrylate, butyl acrylate, sec-butyl acrylate, pentyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, sec-butyl methacrylate, pentyl methacrylate, cyclohexyl methacrylate and fluorinated acrylates and methacrylates such as trifluoromethyl methacrylate, trifluoromethyl acrylate, 2',2',2'-trifluoroethyl methacrylate, 2',2',2'-trifluoroethyl acrylate, 1,1,1,3,3,3-hexafluoroiso
• cross-linking agent refers to a monomer containing at least two reactive groups capable of forming covalent linkages with reactive groups found on at least one of the monomers used to prepare the polymer compositions described herein.
• Suitable reactive groups include, for example, vinyl groups which can participate in the polymerization reaction.
• the reactive groups are typically substituents on a suitable backbone such as a polyoxyalkylene backbone (including halogenated derivatives thereof), a polyalkylene backbone, a glycol backbone, a glycerol backbone, a polyester backbone, a polyamide backbone, polyurea backbone, a polycarbonate backbone, and the like.
• Cross-linking agents for use in the preferred compositions described herein are well known in the art and the particular cross-linking agent employed is not critical.
• the reactive vinyl group is attached to the backbone of the cross-linking agent via an ester bond such as that found in acrylate and methacrylate derivatives such as urethane diacrylate, urethane dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyoxyethylene diacrylate, polyoxyethylene dimethacrylate, and the like.
• vinyl compounds include, by way of example, di- and higher- vinyl carbonates, di- and higher-vinyl amides (e.g., CH 2 ⁇ CH--C(O)NHCH 2 CH 2 NH--C(O)CH ⁇ CH 2 ), divinyl benzene and the like.
• Preferred cross-linking agents include, by way of example, ethylene glycol dimethacrylate, ethylene glycol diacrylate, diethylene glycol dimethacrylate, diethylene glycol diacrylate, triethylene glycol dimethacrylate, triethylene glycol diacrylate, tetradecaethylene glycol dimethacrylate, tetradecaethylene glycol diacrylate, allyl methacrylate, allyl acrylate, trimethylol-propane trimethacrylate, trimethylolpropane triacrylate, 1,3-butanediol dimethacrylate, 1,3-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol dimethacrylate, 1,9-nonanediol
• the cross-linking agent preferably has at least 2 and more preferably from 2 to about 6 vinyl functionalities and preferably has a number average molecular weight of from about 100 to about 2,500. More preferably, the vinyl functionalities are acrylate or methacrylate groups attached to a polyoxyalkylene backbone (including halogenated derivatives thereof), a polyalkylene backbone, a glycol backbone, a glycerol backbone, a polyester backbone, or a polycarbonate backbone.
• a polyoxyalkylene backbone including halogenated derivatives thereof
• compatible non-volatile hydrophilic solvent refers to solvents which have a boiling point of greater than about 70° C. and which are non-reactive either with the reagents employed to prepare the tinted hydrogel material or with the tinted hydrogel material itself.
• Suitable such solvents include, by way of example, water, methanol, ethanol, ethylene glycol, glycerol, N-methyl pyrrolidone, methylene chloride, boric acid esters of polyhydric alcohols and dihydric alcohols and the like.
• Suitable polyhydric alcohols and dihydric alcohols are disclosed in U.S. Pat. Nos. 4,495,313 and 5,039,459 both of which are incorporated herein by reference in their entirety.
• hydrogels derived from a single monomer can be used, copolymeric, terpolymeric, etc. hydrogels are typically employed because the use of more than one monomer provides a ready vehicle to tailor a broad range of properties in the final product for its intended use.
• Examples of copolymeric or higher hydrogels include the polymer compositions set forth in Table I below:
• copolymers, terpolymers, etc. suitable for use herein include tetrafilcon A, polymacon, bufilcon A 45, crofilcon A, surfilcon A, perfilcon A, Netrafilcon A, and the like.
• the hydrogel materials prepared by the methods of this invention are preferably cross-linked and, accordingly, one of the components of a preferred monomer/leuco sulfate ester of a vat dye is a cross-linking agent.
• the cross-linking agent is employed in an amount sufficient to provide a cross-linked product but preferably is employed in an amount of from about 0.1 to about 5 weight percent and more preferably from about 0.1 to about 0.5 weight percent based on the total weight of the monomer(s) and leuco sulfate ester(s) employed.
• the composition is then converted to the tinted hydrogel material in one of two methods as set forth below.
• oxidizing initiators suitable for use in the methods described herein include, by way of example, non-chemical initiators such as ultraviolet (UV) light which can initiate photoxidation of the leuco sulfate ester of the vat dye to the insoluble vat dye and simultaneously initiate polymerization.
• non-chemical initiators such as ultraviolet (UV) light which can initiate photoxidation of the leuco sulfate ester of the vat dye to the insoluble vat dye and simultaneously initiate polymerization.
• UV ultraviolet
• the use of high temperatures in an oxygen atmosphere can initiate oxidation.
• oxidizing initiators examples include, for instance, chemical oxidizing initiators such as t-butyl peroxy pivalate (TBPP), t-butyl peroxy neodecanoate (TBPN), benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, acetyl peroxide, stearoyl peroxide and the like.
• chemical oxidizing initiators such as t-butyl peroxy pivalate (TBPP), t-butyl peroxy neodecanoate (TBPN), benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, acetyl peroxide, stearoyl peroxide and the like.
• TBPP t-butyl peroxy pivalate
• TBPN t-butyl peroxy neodecanoate
• benzoyl peroxide
• a chemical oxidizing initiator when employed, it is employed in sufficient amounts to both initiate oxidation of the leuco sulfate ester of the selected vat dye(s) as well as to initiate polymerization of the monomer composition.
• the chemical oxidizing initiator is employed at from about 0.01 to about 1 weight percent relative to the total amount of monomer(s) (including any cross-linking agents) and leuco sulfate ester(s) in the composition.
• oxidation of the leuco sulfate ester of the vat dye to the water insoluble vat dye and polymerization of the monomer composition can be initiated sequentially.
• oxidation of the leuco sulfate ester of the vat dye is initiated prior to initiation of polymerization of the monomer composition by use of an initiator more selective for oxidation than polymerization under the conditions employed.
• selective oxidation initiators are known in the art and include, by way of example, low quanta of UV light, oxidants having low polymerization capacity, and the like.
• polymerization of the monomer composition is then initiated by adding a polymerization initiator to the reaction medium and/or subjecting the reaction medium to polymerization conditions.
• a polymerization initiator are well known in the art and include thermal initiators, UV initiators, as well as ⁇ irradiation, or electron beam irradiation.
• Thermal polymerization initiators are typically added to the mixture of monomers under an inert atmosphere (e.g., argon) and maintaining the mixture at an elevated temperature of from about 20° C. to about 75° C. for a period of time from about 1 to about 48 hours. Suitable thermal initiators are described above and are employed in the amounts also described above.
• an inert atmosphere e.g., argon
• Polymerization achieved by either electron beams or ⁇ irradiation does not require the use of an initiator and the formulation to be polymerized is merely exposed to sufficient quantities of electron beam or ⁇ irradiation under polymerization conditions using conventional methods.
• polymerization of the monomer mix can precede oxidation of the leuco sulfate ester of the selected vat dye merely by employing a polymerization reagent which polymerizes the monomer composition prior to oxidizing the leuco sulfate ester.
• the sulfate ester is dispersed/solubilized throughout the polymer composition and is subsequently oxidized by conventional methods, e.g., exposure to light, hydration of the xerogel with an oxidizing solution such as an aqueous sodium nitrite solution, and the like.
• completion of the oxidation is accomplished by heating the polymer composition in an autoclave at a temperature of from about 105° C. to about 130° C. for from about 10 minutes to about 1 hour. The completion of the oxidation process finalizes the color or hue of the composition.
• a post-polymerization curing procedure is also optionally employed to complete the polymerization process which typically increases the hardness of the polymer.
• the post-curing procedure can comprise heating the polymer to a temperature of from about 60° C. to 130° C. for a period of from about 2 to about 24 hours.
• the resulting polymer material typically does not contain more than trace amounts of water and is referred to in the art as a xerogel composition.
• This composition is then hydrated via conventional techniques to incorporate at least 10 weight percent water into the polymer material thereby converting the polymer from a xerogel composition to a hydrogel composition.
• the requisite amount of water or other compatible non-volatile hydrophilic solvent required for hydrogel formation can be incorporated directly into the monomer/leuco sulfate ester mixture prior to oxidation and polymerization.
• the water or other compatible non-volatile hydrophilic solvent can assist in solubilizing the leuco sulfate ester and, when employed, are preferably employed up to about 75 weight percent based on the total weight of the resulting polymer composition.
• water it is contemplated that subsequent oxidation and polymerization will result directly in hydrogel formation without the need for a separate hydration step.
• hydrophilic polymers described herein are particularly useful in the manufacture of hydrogel materials which are conventionally employed in ophthalmic devices such as contact lenses and intraocular lenses. Preferably, these hydrophilic polymers are used in the methods of this invention to manufacture contact lenses. Additionally, the hydrophilic polymers, prior to hydration, are useful for the absorption of water in such products as disposable diapers, etc.
• Examples 1, 2 and 6 illustrate simultaneous oxidation of the leuco sulfate ester to the insoluble vat dye and polymerization of the monomer composition followed by hydration of the resulting polymer composition.
• Example 3 illustrates the sequential initiation of oxidation of the leuco sulfate ester followed by initiation of polymerization of the monomer composition and then hydration of the resulting polymer composition.
• Example 4 illustrates the sequential initiation of polymerization of the monomer composition followed by initiation of the oxidation of the leuco sulfate ester followed by hydration of the resulting polymer composition and hydration of the resulting polymer.
• Example 5 illustrates the simultaneous oxidation of the leuco sulfate ester of the vat dye and polymerization of the monomer composition in the presence of water directly resulting in the hydrogel material.
• a solution of 0.1 weight percent of the leuco sulfate ester of Vat Green #1 dye was made up in hydroxyethyl methacrylate containing 0.5 weight percent ethylene glycol dimethacrylate as a cross-linking agent. A brownish fluorescent green solution formed. To this solution was added 0.9 weight percent azobis isobutyronitrile and the solution was then poured into lens molds and polymerized/oxidized by thermal treatment at 60° C. for five hours. The resulting polymer composition was then treated by a post-cure step which comprised heating the composition at 90° C. for two hours.
• the polymeric material was then released from the molds and hydrated in buffered saline to provide a tinted hydrogel material in the form of contact lenses having a slight aqua green coloration which coloration is resistant to autoclaving and which material contains about 38 weight percent water.
• a solution of 0.1 weight percent of the leuco sulfate ester of Vat Blue #6 dye was made up in hydroxyethyl methacrylate containing 0.5 weight percent ethylene glycol dimethacrylate as a cross-linking agent. An orange solution was formed. To this solution was added 0.9 weight percent azobis isobutyronitrile and the solution was then poured into lens molds and polymerized/oxidized by thermal treatment at 60° C. for five hours. The resulting polymer composition was then treated by a post-cure step which comprised heating the composition at 90° C. for two hours.
• the polymeric material was then released from the molds and hydrated in buffered saline to provide a tinted hydrogel material in the form of contact lenses having a blue coloration which coloration is resistant to autoclaving and which material contains about 38 weight percent water.
• a solution of 0.1 weight percent of the leuco sulfate ester of Vat Blue #6 dye was made up in hydroxyethyl methacrylate containing 0.5 weight percent ethylene glycol dimethacrylate as a cross-linking agent. An orange solution formed. To this solution was added 0.3 weight percent tert-butyl peroxy neodecanoate. Before dispensing, the monomer solution was maintained at room temperature for 30 minutes whereupon the solution turned to a blue coloration evidencing that at least a portion of the leuco sulfate ester was oxidized to the insoluble vat dye. The solution was then poured into lens molds and polymerized by thermal treatment at 60° C. for five hours. The resulting polymer composition was then treated by a post-cure step which comprised heating the composition at 90° C. for two hours.
• the polymeric material was then released from the molds and hydrated in buffered saline to provide a tinted hydrogel material in the form of contact lenses having blue coloration which coloration is resistant to autoclaving and which material contains about 38 weight percent water.
• a solution of 0.1 weight percent of the leuco sulfate ester of Vat Orange #5 dye was made up in hydroxyethyl methacrylate containing 0.5 weight percent ethylene glycol dimethacrylate as a cross-linking agent.
• To this solution was added 0.9 weight percent azobis isobutyronitrile and the solution was then poured into lens molds and polymerized/oxidized by thermal treatment at 60° C. for five hours.
• the resulting polymer composition was then treated by a post-cure step which comprised heating the composition at 90° C. for two hours.
• the polymeric material was then released from the molds and hydrated in buffered saline to provide a clear hydrogel material in the form of contact lenses which material contains about 38 weight percent water.
• the hydrogel material Upon contact with an aqueous solution of sodium nitrite, the hydrogel material became a bright orange color which coloration was resistant to autoclaving.
• Example 1 The procedure of Example 1 is repeated except that the composition comprising the monomer, the cross-linking agent and the leuco sulfate ester of Vat Green No. 1 dye further comprises about 38 weight percent water. Upon simultaneous oxidation and polymerization, the resulting polymer is a tinted hydrogel material without the need to employ a separate hydration step.
• the lenses were released from the lens mold to give blue colored dry lenses.
• the lenses were then extracted and hydrated to provide for tinted hydrogel contact lenses having 74 weight percent water which lenses were stored in a buffered saline solution.
• the blue coloration of the lenses was resistant to autoclaving.
• the dye could be dissolved in the more hydrophilic monomer, N-vinyl pyrrolidine, and the remaining monomers and the initiator added and mixed prior to dispensing into contact lens molds.
• the monomer mix could contain from 0 to 2.0% of a conventional functionally UV absorbing monomer, and cured at temperatures ranging from 35° C. to 70° C.

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• Optics & Photonics (AREA)
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• 1995
  • 1995-05-19 US US08/446,559 patent/US5534038A/en not_active Expired - Lifetime
  • 1995-05-26 AU AU26569/95A patent/AU2656995A/en not_active Abandoned
  • 1995-05-26 EP EP95921509A patent/EP0764190B1/fr not_active Expired - Lifetime
  • 1995-05-26 CA CA002190153A patent/CA2190153A1/fr not_active Abandoned
  • 1995-05-26 ES ES95921509T patent/ES2162920T3/es not_active Expired - Lifetime
  • 1995-05-26 DE DE69522220T patent/DE69522220T2/de not_active Expired - Fee Related
  • 1995-05-26 WO PCT/US1995/006824 patent/WO1995034605A1/fr not_active Ceased
  • 1995-05-26 JP JP8502213A patent/JPH10501310A/ja not_active Ceased

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